Moritz Zaiss

CEST MRI is regarded as an exciting topic in the field of biomedical imaging. Its major advantage is imaging of physiological and molecular information with spatial resolution comparable to that of conventional MRI. Correlations of CEST signals with protein content and protein structure, metabolite concentration (especially glucose), as well as pH have made CEST an interesting imaging modality for studies of cancer: Metabolic changes indicate tumor activity, Protein content is a measure of increased cellularity during tumor infiltration; furthermore, there is a correlation between gradients in pH and tumor migration.

For all CEST experiments the magnetization must be prepared by saturation which takes several seconds to build up. Subsequently this magentization state must be read out as quickly as possible before it is lost again. Thus, one major project that forms the basis of all subprojects is the development of fast imaging readouts.

Hand in hand with sequence development , evaluation must be refined; evaluation software is shared on our project webiste www.cest-sources.org.

CEST allows MRI imaging of protein content, conformation and denaturation. All of these might be interesting markers in brain tumors as well as other pathologies, especially in tumors it might overcome the need for contrast agents (see Figure 1). In addition, protein signals have a correlation with pH that is investitgated for use of a pH-weighted imaging.